CNC Milling Aluminum

VT machining provides CNC Milling Aluminum for customers who need accurate, repeatable Aluminum components. Because Aluminum is lightweight, excellent machinability, good corrosion resistance, we adapt the process to suit — controlling the variables that matter for this alloy.

CNC Milling Aluminum at VT machining
CNC Milling Aluminum — produced in-house at VT machining

CNC Milling Capability for Aluminum

  • 3-, 4- and 5-axis capability
  • Tolerance to ±0.01 mm
  • Pocket/slot/contour features
  • Spindle speeds to 12,000+ rpm

Aluminum Material Data

Aluminum — typical properties, quoted for 6061-T6
Density2.70 g/cm³
Tensile strength310 MPa
Yield strength (0.2%)276 MPa
Hardness95 HB
Melting point582–652 °C
Thermal conductivity167 W/m·K
Thermal expansion23.6 ×10⁻⁶/K
Electrical conductivity43%
Machinability (C36000 = 100%)190%
Grades we run6061, 6082, 6063, 7075-T6, 5052, 2024-T3, MIC-6 cast plate

Published typical values for 6061-T6. Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.

Machining Aluminum — what actually causes trouble

Thin walls relax after roughing. We rough, let the part stabilise, then finish — otherwise a 1.5 mm wall bows by more than the tolerance it was cut to.

How CNC Milling Aluminum Works

Rotating multi-flute cutters remove material as the Aluminum workpiece is driven through programmed tool paths on 3-, 4- or 5-axis machining centres. Climb milling, step-over and depth-of-cut are set so chip load stays in the ideal band for the alloy.

Every job begins from your CAD model or 2D drawing. Fixturing and tool paths are planned so the most critical dimensions are produced in the most rigid, repeatable setup. Critical dimensions are checked on the first part and monitored through the run.

Achievable Tolerances for CNC Milling Aluminum

CNC Milling Aluminum — achievable tolerances
FeatureStandardPrecision
Linear dimension (< 100 mm)±0.05 mm±0.010 mm
Linear dimension (100–300 mm)±0.10 mm±0.025 mm
Hole diameter (reamed)H9H7
True position of hole pattern±0.10 mm±0.025 mm
Flatness over 100 mm0.05 mm0.015 mm
Perpendicularity0.10 mm0.020 mm
Surface finish, as machinedRa 1.6 µmRa 0.4 µm

Standard is what a normal quotation assumes. Precision is available on nominated features and is priced separately, because it needs extra setups, in-process gauging and CMM verification. Call out only the features that need it — blanket-tightening a drawing is the single most common reason a quote comes back expensive.

Secondary Operations & Finishing

We complete Aluminum components with the secondary steps your drawing calls for. We arrange heat treatment, surface treatment, marking and assembly as needed. Tell us the final spec and we will plan the full route so parts arrive ready to use.

CNC Milling Quality & Inspection

Consistent quality comes from disciplined process control. Critical dimensions on Aluminum parts are checked in-process and verified at final inspection using calibrated instruments and, where required, CMM measurement. Full documentation — dimensional reports, mill certs, FAIR — is available when your programme needs it.

Design Tips for CNC Milling Aluminum

A few design choices make a real difference to cost and quality. Generous internal radii, sensible pocket depth-to-width ratios and avoiding very thin unsupported walls all reduce cost and improve accuracy in Aluminum. If you send your model early, we will return practical DFM feedback before you commit to production.

Working with Aluminum

Aluminum offers a useful combination of properties: it is lightweight, excellent machinability, good corrosion resistance. Those characteristics shape how we approach milling — from tool and parameter selection to work-holding and coolant.

If your application is sensitive to alloy condition, we agree the specification in writing and document it. Stock is sourced from reputable suppliers so what you order is what you receive.

CNC Milling Tolerances & Surface Finish

For CNC Milling, dimensional and positional tolerances around ±0.01 mm are routine, tightening toward ±0.005 mm on precision setups. Surface finish on machined faces typically falls in the Ra 0.4–1.6 µm range depending on tooling and pass strategy.

Final tolerances are governed by the material's behaviour, wall thickness and overall stiffness. We give honest DFM feedback if a callout would be costly or better achieved another way.

Applications of CNC Milling Aluminum

CNC Milling of Aluminum supports parts across aerospace, medical, automotive, electronics, semiconductor, energy and general industrial sectors. We scale from one-off prototypes to ongoing production while holding the same quality.

How to Order CNC Milling Aluminum

Ordering Aluminum parts is straightforward. Provide the drawing, material, quantity and any certification needs. Our engineers reply — in English — with feasibility, pricing and a realistic lead time, usually within one business day.

Parts We Have Run in Aluminum

Three representative CNC Milling Aluminum jobs, with the callouts that actually drove the process plan. Yours will differ — these are here so you can judge whether your part is in our range before you spend time on an RFQ.

Manifold block

Material
Aluminum
Size
120 × 60 × 45 mm
Key callouts
Cross-bore intersection ±0.05 mm, ports G1/8", leak-tested to 10 bar
Batch
80 pcs

Deburred internally with a brush tool; a burr at a cross-bore is what fails the leak test.

Heat sink base

Material
Aluminum
Size
200 × 100 × 8 mm
Key callouts
Fin thickness 1.2 ±0.05 mm, base flatness 0.03 mm
Batch
500 pcs

Fins cut with a slotting cutter in one pass to avoid the deflection a step-over leaves.

Optical mount plate

Material
Aluminum
Size
160 × 160 × 12 mm
Key callouts
Hole pattern true position ±0.02 mm, flatness 0.01 mm
Batch
40 pcs

Roughed, stress-relieved overnight, then finished — the plate is too thin to hold flatness in one hit.

Finishing Options for Aluminum

Finishing options available with this material
FinishThickness / effectWhy it gets specified
Clear anodise (Type II)5–25 µmCorrosion protection, keeps the natural colour
Colour anodise10–25 µmBlack, red, blue, gold; add 0.02 mm to close tolerances
Hard anodise (Type III)25–50 µm60–70 HRC surface, grows 50% into the part
Chromate / Alodine 1200< 1 µmConductive, meets MIL-DTL-5541
Powder coat60–120 µmRAL colours, needs 0.3 mm clearance on mating features
Deburr / edge break0.05–0.3 mmAll parts unless the drawing says otherwise
Bead blastRa 1.6–3.2 µmUniform matt finish, hides tool marks
Laser markingPart number, lot code, data matrix
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No drawing yet? Build one in the browser.

Set the metal, dimensions and features, watch the 3D model update as you type, then switch to the 2D sheet to add dimensions and tolerances. Download it or send it straight to us with your RFQ.

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What We Need to Quote CNC Milling Aluminum

  • GeometrySTEP or IGES for the 3D model, plus a PDF drawing if you have tolerance callouts. A dimensioned sketch is enough to start.
  • MaterialThe exact Aluminum grade and condition — temper, heat-treat state or hardness. If you are not sure, tell us the function and we will suggest one.
  • QuantityPrototype count and the expected annual volume. Both change how the part is made and therefore what it costs.
  • TolerancesWhich features are critical. Everything else runs to our standard tolerance, which is what keeps the price sensible.
  • FinishSurface treatment, cosmetic requirements, and any faces that must be masked.
  • DocumentsWhether you need a material certificate, dimensional report, FAIR or PPAP with the shipment.

Missing something from the list is not a problem — send what you have. We will come back with the specific questions rather than a generic form.

Other Metals for CNC Milling

Other Processes for Aluminum

Send the drawing, the Aluminum grade and the quantity. You get pricing, lead time and any DFM notes back — usually within one business day.

Request a Quote

Frequently Asked Questions

What material thickness or size range suits CNC Milling Aluminum?

We machine Aluminum across a broad size range; share your part envelope for confirmation.

Why is Aluminum a good choice for CNC Milling?

Aluminum is lightweight, excellent machinability, good corrosion resistance, which makes it well suited to CNC Milling. We tune the process to the alloy so the finished Aluminum machining part meets your dimensional and functional requirements.

What surface finish is achievable on Aluminum with CNC Milling?

Surface finish on Aluminum is controlled to your specification; we confirm the achievable Ra against your callout.

Which industries use CNC Milling Aluminum parts?

CNC Milling Aluminum parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise Aluminum components are required.

What is the typical lead time and minimum order for CNC Milling Aluminum?

CNC Milling prototypes for Aluminum can be produced quickly and scaled to series production. Send your drawing and quantity and we will advise lead time and any minimum order.

What is CNC Milling Aluminum and how is it done?

CNC Milling Aluminum refers to multi-axis milling cutters remove material to produce prismatic features, pockets, slots and contoured 3D surfaces. Applied to Aluminum — lightweight, excellent machinability, good corrosion resistance — VT machining produces each part to your CAD drawing, selecting parameters from your tolerance, finish and quantity requirements.